1. Field of the Invention
The present invention relates to an oil cooling system for an internal combustion engine and, in particular, to the improvement whereby temperature and viscosity of the oil is regulated particularly during the initial warmup time of the engine.
2. Description of the Prior Art
Until an internal combustion engine is fully warmed up, the oil flowing therethrough is not at its optimal viscosity and temperature, e.g., to insure that any water in the system will not condense. In addition, it is important that the temperature of the oil not be permitted to rise beyond permissible limits; therefore oil coolers are used, either as part of the radiator system or as a separate oil cooler. While the maximum cooling effected by the air coolers are sufficient to cool the oil adequately at normal operating temperatures of the engine, they also prevent the most rapid rise in temperature of the oil during initial warmup of the engine. Therefore, the likelihood of water condensing and causing corrosion exists.
In addition, it is also preferable to reduce the viscosity of the oil as quickly as possible in order to decrease the load on the battery and the starter. Other desirable results of increased viscosity include an increase of gas mileage, and as an aid in preventing decrease in horsepower by reducing the load on the engine.